Chesapeake’s oyster reefs shellacked by years of dredging

By Kent Mountford
onJune 01, 2001

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I walked out to the blighted waterfront using directions from Susan Langley, state underwater archaeologist for Maryland. There, adjacent to a sailing club’s floating pier and Baltimore’s Museum of Industry, amid the rubble and marine debris from centuries of intense use by the Chesapeake’s maritime industries, was the wreck of a once-graceful steamer.

The ship, the Governor McLane, was brought here by the early 1970s to be cut up for salvage at what was once the Hercules Shipyard. Although stripped of her superstructure and decks, the McLane’s graceful sheer line, high sharp bow and lovely fantail stern echo the classic taste of naval architects in the last third of the 19th century.

Named for former Maryland Gov. Robert M. McLane, the ship was a central figure in the history of the Chesapeake’s natural resources as flagship of Maryland’s Oyster Navy, a force made necessary because of conflicts resulting from the diminution of the Bay’s great shellfish resource.

Her history begins with the decimation of New England’s oyster beds hundreds of miles away from the Chesapeake. With large dredges and no regulation at the time, Cape Cod and Long Island oystermen entered the Chesapeake about the middle of the 19th century and began to literally mine the estuary’s then-extensive oyster “rocks” or reefs. Hard feelings were quick to develop when local watermen saw outsiders with larger and more efficient gear sweep in and take the best of their resources.

The Civil War intervened during this period, but not long after, Maryland’s and Virginia’s oystermen took a page from their competitor’s books and began a rapacious harvest of their own.

Harvesting until that time had been done largely with tongs, using variations of the Native American’s log canoe. The canoe was originally a single log hollowed out with the aid of fire and scrapers, but later became a longer and more beamy vessel carved from an amalgam of three, and sometimes five, logs. A few of these are still sailing as recreational log canoes.

Small, log canoes were perfectly suited for tonging oysters by hand where working depths were 15–20 feet, but local watermen, after watching the success of New England dredgers, realized that larger boats would give them a harvest advantage.

The resulting large, log-built vessels were shaped as gracefully as the builder’s eye and fancy could determine. They featured a two-masted rig, and were limited in width by the number of logs which could be reasonably joined side to side, and in freeboard by “rising planks” added along the sides above the logs. They were called “bugeyes,” (The origin of that name is obscure.) and were usually slim vessels and pretty good sailors, a competitive advantage when returning the oysters to market.

Bugeyes were also somewhat “tender” in sailor’s jargon, and could not bear a great press of sail in heavy winds without the threat of capsizing. For this reason, they were almost entirely rigged with the triangular, narrow-headed “Bermuda” or “leg-of-mutton” sail which is pointed at the top to minimize weight aloft and decrease the heeling (tilting) movement of the gaff-headed rig normally seen on Bay schooners. The result was a very efficient speed for harvesting oysters that would only be exceeded with the addition of engines, which made sufficient wind to power heavy dredges across the rocks irrelevant.

As the easy and abundant harvests declined, the states began to compete for each others’ resources, with Virginians making forays into Maryland waters of the Potomac and Marylanders into Virginia’s Tangier and Pocomoke Sounds.

Oyster “pirates,” with no loyalty to either jurisdiction, made forays wherever they could get away with it, and locals formed militia to defend beds adjacent to their villages. Maritime historian M.V. Brewington reports that during such conflicts, a curved piece of boilerplate encircled the pirate helmsman, while the remaining crew stayed below until out of range.

By 1868, the Maryland General Assembly intervened and commissioned a State Oyster Navy, with a cadre of 50 men, charging it to keep the peace, and to especially enforce the culling laws designed to preserve small oysters until they were of productive age.

Appointments to these posts were considered political plums and were tightly controlled by the ruling political party. As a result, some of the officers were less than aggressive in pursuing the oyster’s cause. One commander allowed that during the late Civil War, he’d spent good money to hire a replacement and avoid combat and that at his present advanced age, he was not about to take any foolish risks.

The oyster harvest continued at brutal and unsustainable levels.

Labor practices in the Bay region, especially Baltimore, became exploitive and new immigrants, chiefly those from Germany who didn’t speak English, were shanghaied aboard dredge boats and forced to work long hours at low pay. Usurious charges against wages advanced for board and ragamuffin clothing kept these poor men in perpetual debt and servitude, working through winter’s worst conditions on a dangerous Bay.

Legend has it that at a voyage’s end, many were “paid off with the boom” —swept overboard by an intentional jibe which brought the mainsail and its heavy spar across the deck like a scimitar. Once in the cold water, with the skipjack sailing away, men were simply left to drown.

The skipjack, regarded with teary-eyed nostalgia, as harking back to a time of greater oyster abundance, was really a product of the resource’s collapse. When larger and more expensive bugeyes were no longer economically viable, many were rigged down and turned into “buy boats,” serving as wholesale merchants and collectors of oysters dredged by other boats.

The buy boat captains set prices based on the market as they saw it, with a markup sufficient to pay their freight and assure a profit when the catch was carried to shucking houses ashore.

Skipjacks were shoal draft, with hulls planked in sawn pine boards; were cheaper to build; had less rigging and sails to maintain; and could be handled by smaller crews.

They were built to harvest at minimum cost with unskilled labor and while never intended to sail for 100 years, a few remnant boats today have managed to do so. In a sense, they were scavengers coming in to make a final kill on the Bay’s remnant oysters.

The average 19th century skipjack captain and crew understood only that harvests were decreasing and that they’d better get all they could. John R. Wennerstein, in his book, “The Oyster Wars of the Chesapeake Bay,” reports a folk saying: “Get it today! Hell with tamar.’ Leave it till tamar,’ sombody else’ll get it.”

In 1870, the “Hunter and Davidson Report” said that oyster resources of the lower Bay were already depleted by the disregard of culling laws designed to return small, immature oysters to the beds so that they might continue growing.

In order to bring some regulation to piratical harvesters, the Maryland Oyster Law of 1872 required that all canoes authorized to tong for oysters paint their numbers below the gunwale, a practice still followed with modern boat registrations.

The so-called “Line of ‘77” (1877), the markers for which are still maintained today, separated Maryland and Virginia’s oyster beds. Virginia got the better of the Tangier and Pocomoke Sound beds, embittering Marylanders, who felt the loss of grounds upon which they fervently believed “their prosperity had rested.”

In 1878, Maryland petitioned the U.S. Navy for the services of a surveyor who could help evaluate the remaining oyster resource.

On Oct. 15th, Lt. Fransis Winslow arrived at Annapolis and boarded the Oyster Navy’s old side-paddlewheel steamer, Leila, which would become his working platform. His quiet, businesslike demeanor earned the watermen’s respect and his work was uncontested.

Winslow confirmed that the resource was in danger: On some “beds,” he found only one oyster for each three square yards of bottom — pretty slim dredging. He warned against both taking oysters under 3 inches and failing to replenish the millions of pounds of shell being mined.

The harvest in 1884 was 15 million bushels.

Conflicts were increasing among Virginia and Maryland oystermen, as well as the oyster pirates who formed roaming bands in the Choptank and Potomac. In the winter of 1889, 12 men died in altercations on Hog Island Flats. The overall harvest fell that year to 9.945 million bushels, and has continued downward.

The Maryland Oyster Navy at one point had two steamers, four schooners and six sloops.

The Governor McLane replaced Leila, whose “hull, engine and boiler are very badly constructed … she is constantly needing repairs.”

Built of iron in Philadelphia in 1884, the McLane was 114 feet long, 21 feet in beam and had a draft of 9.2 feet. Although she displaced 161 gross tons, she was screw-propelled and could steam at 13 knots, outrunning almost all of the Bay’s brigand vessels. She was armed with a 12-pound howitzer on her foredeck that saw substantial service during her patrols and combat missions.

Leila was sold out of the service for a paltry $850. The McLane led Maryland’s little Navy until 1932, excepting her duty on coastal patrol during World War I.

The path followed by the Chesapeake’s oyster industry over the century subsequent to McLane’s commissioning is well-documented: the inexorable decline in harvests, the destruction of the three-dimensional character of the reefs and the introduction of two virulent diseases.

The Potomac, based on a very old River Compact, has always been in Maryland, with the Virginia line running along the river’s southern shoreline.

Oyster piracy continued along the Potomac through the 1940s and into the ’50s, especially along a 25-mile stretch south of the Route 301 Harry Nice Bridge. A so-called “Mosquito Fleet” of extremely fast inboard boats armed with “poaching dredges” outran police, and worked at night and without lights, retreating into ports on the Virginia side, just outside the reach of Maryland law.

As post-World War II outboard motor technology caught the fancy of boaters, high-powered Mercury or Johnson motors continued to outpace the enforcers. It was a colorful time, even though men were shot and killed, and the oyster resource continued its inexorable decline, reducing the industry to a sorry state.

To help manage oyster diseases, shells from shucked oysters or dredged from old deposits were placed in lower Bay sites like Kedges Strait on the Eastern Shore and, when an acceptable set of spat (juveniles) have taken hold, these seed oysters are taken up and replanted elsewhere. I view this as not far from the put-and-take fishery conducted in many freshwater lakes and streams.

Meanwhile, there is not enough of this recycled shell to go around.

A real appreciation for the oyster’s role in the Bay’s ecology is dated by some to University of Maryland scientist Roger Newell’s paper which compared the once-great filtering capacity of their pre-colonial population to the modern state where biomass may be reduced to 1 percent of its original value.

Scientists, such as William Jennings Hargis and colleagues at the Virginia Institute of Marine Science and Gary Smith at Maryland’s Oxford Cooperative Shellfish Laboratory, reconstructed the geometry of the Bay’s oyster reefs from 19th century navigation charts and soundings using modern sonar techniques. They began to understand how these reefs might have functioned. Perhaps it would be possible to rebuild them, and the resource.

Sleeping undisturbed, primarily in the upper Chesapeake, near Pooles Island, but also at sites in the lower Bay, are ancient, partially fossilized deposits of oyster reefs past: Reefs that have accumulated billions of pounds of shell over millennia as shellfish grew, reproduced and died atop one another as sea level slowly rose, inundating the ancestral Susquehanna River gorge.

It is amazing to me that these very old deposits have never been properly studied by geologists, paleontologists or ecologists to unlock the Chesapeake history they must contain. We do not even clearly know how old they are, although Maryland Geological Survey Scientist Jeff Halka suggested that they are probably around 5,000 years old. Paleontologist Dr. Ralph Eshelman muses: “There must be artifacts in that stuff.”

Ancient or not, they are being heavily mined and have been for about four decades, since their recognition as a source of good calcium material. The C.J. Langenfelder Company has mined hundreds of thousands of bushels of this “fossil” shell under permit from Maryland during that time.

The larger portion of their extraction goes for a variety of industrial purposes: a mineral source, poultry feed additives. It is even a constituent of the growing media for Paphiopedilum or “slipper” orchids. You can buy it, processed and branded under other names such as American Stone Mix Inc., which sells it as “pure reef oyster shell.” It’s also in many farm supply stores and can be added to chicken feed at 110 pounds of shell to a ton of feed.

Part of the Langenfelder’s bargain is that a sufficient quantity is sold to Maryland (2.5 million bushels in the current permit round) and formerly to Virginia as a natural substrate to be barged down the Bay and blasted off the deck with fire-hoses where it falls to the bottom in locations showing promise for a good oyster set. Sales out of state are less likely today because the resource is accompanied by an immense amount of political capital, thanks to new programs purporting to re-create the Bay’s once vast emergent oyster reefs.

Boaters in the Upper Bay off Pooles Island or Fairlee Creek can see oyster shell dredging almost continuously during summer months. Shells, thousands of years old, (and containing history lessons about the Bay’s past that are unread) are washed of fine sediments using Bay water and accumulated in barges tied along either side in piles a dozen feet deep in minutes. Barge after barge heads off, propelled by tugboat and bound for processing or down the Bay for “planting.”

Proponents for the open water disposal of navigational dredge spoils are accused of releasing unwanted nutrients into the water. They point, in turn, to “fossil” shell dredging which has gone on for decades and ask if that is a source of pollutants as well.

Certainly, resuspended sediment is turned up as the shell dredge cuts as much as 25 feet deep into old deposits.

The Maryland DNR has plans to assess the potential for washed fines, (resuspended sediments) or the exposure of ancient sediments in the dredge-cut to release significant nutrients.

The Chesapeake Bay Program has set a goal to increase the Bay’s standing crop of oysters by tenfold by 2010. This represents a very large financial commitment, many millions of dollars, about which I have some misgivings.

You can take the filtering ability of one, good-sized oyster and rapidly calculate, as Newell did, that some number of millions could filter the whole Bay, clarifying it and sending sequestered nutrients to the bottom as pelletized “pseudofeces.” This is too simple. It’s actually quite uncertain that even if we restored oyster reefs to their pre-colonial, or even 19th century levels that their filtering capacity would significantly heal the Chesapeake’s water quality problems.

Jeroen Gerritsen, A.F. Holland and Dave Irvine, in 1994, modeled benthic-filtering capacity and concluded that water circulation patterns in Maryland’s portion of the Chesapeake would at least keep large amounts of pollution-stimulated plankton away from alongshore reefs. They further suggest that existing populations of bivalve and other invertebrate benthos already consume a significant portion of the Bay’s plankton. Perhaps plankton is simply growing too fast on the nutrients we dump in the estuary for filter feeders to keep pace.

It might still be worth trying, but siting artificial reefs is a delicate process, one which nature did for tens of thousands of years without human intervention.

With the modern estuary subject to severe deep-water oxygen depletion in summer as a result of excess plankton loads, the threat of losing a portion of our investment, through unwise placement is significant.

Hunter Lenihan and colleagues in North Carolina found that when oxygen-poor water intruded upon artificial reef structures during weather events, they had death rates of 50 percent, 80–85 percent and at some sites, 100 percent. Reefs shallower than about 5 meters (18–19 feet) had a survival rate that increased closer to the surface, and the higher the relief above bottom the better, which is consistent with our understanding of how the originals functioned.

Meanwhile, the Bay Program has in place a committee structure that proposes and accepts the reconstruction of oyster reefs at sites subject to evaluation and approval, a process that has received a lot of media attention.

Some progress has been made in breeding the American eastern oyster, (Crassostrea virginica) for resistance to the two virulent oyster diseases MSX and Dermo by facilities like the Haskin Shellfish Laboratory in Bivalve, NJ. This, in my opinion, is the only real route to restoration.

I share the concern about introducing foreign oyster species to the Bay, something that has proven unwise with hundreds of other species. Crassostrea gigas, introduced by an unwitting researcher in the mid-20th century, is the likely source of the deadly MSX protozoan parasite.

The limited supply of the Upper Bay fossil oyster reefs has spurred Virginia to consider reopening its old ancient shell deposits. VIMS has done studies on several reconstructed artificial reef habitats, one built of broken shell from shucked offshore surf clams (Spisula solidissima) which does not seem to contain the same favorable nooks and crannies as oyster shell. Young oysters on natural shell, especially those sheltering inside these small interstices, seem to fare well against natural predators and other stresses, such as exposure to drying and heat on the exposed tops of emergent reefs.

Ironically, our society having in its collected ignorance destroyed this once remarkable but unappreciated resource, is also considering less conventional alternatives to rebuild the reefs. It seems a bit disingenuous to dump the waste of our crushingly large culture into the Chesapeake Bay on the premise that this will restore the oyster population.

Nonetheless, structures made from a demolished bridge, cement bound fly-ash (a byproduct from the power plant combustion of coal), and the fragmented remains of toilet bowls being replaced by low-flush versions have all been used or are proposed, at least for the non-living internal cores of reefs that eventually might be covered with a veneer of oyster shell.

A man named John E. Helldorfer contacted me in November 2000 through St. Mary’s College of Maryland about his proposal to use shaped units of concrete-consolidated human cremains (ashes) as a building block for artificial reefs. His concept of a living reef based on dead humans seems flippant at first glance, but when you get right down to it, an oyster reef even partly composed of cremains would suit me just fine as a resting place.

I’d rather like to think a thousand years from now that millions of oysters were forming my memorial. And, we do waste a lot of ground for burying ourselves in coffins and vaults, with no environmental side benefit. I guess if it really works, so what?

We are wont, as an engineering-oriented species, to declare imminent victory based upon innovation and crash programs with measurable goals to restore our own damage to the Bay. But I remain watchful and still to be convinced how well this approach will work for the beleaguered oyster!

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About
Kent Mountford

Dr. Kent Mountford is senior scientist for the Chesapeake Bay Program in Annapolis.